1. Field of the Invention
The present invention relates to a barcode communication interface system for transmitting barcode information received from a barcode decoder to a host computer. In particular this barcode communication interface system and method transmit barcode information received from a barcode decoder in an asynchronous manner by using an asynchronous communication controller.
2. Description of the Prior Art
In general, a barcode reader comprises a barcode detector that detects a barcode and a barcode decoder that decodes the barcode.
The barcode detector scans the barcode by a laser beam and uses a photodiode to detect the reflected laser beam. The detected signal is amplified and differentiated and then converted into a digital signal through a comparator. The decoder receives this digital signal from the barcode detector, converts it into the original barcode information signal, and then transmits the signal to a host computer.
Most conventional communication interface systems are NOT compatible with both the gun-type and the fixed-type barcode reader. Since the communication interface system must be individually adapted to work with a particular type of barcode reader, the circumferential circuits for processing and transmitting the output signals of the decoder to the host computer are relatively complicated, causing the whole circuit configuration to be complicated. Moreover, in order to execute a serial communication in an asynchronous fashion by using a RS-232C, an extra power source (.+-.10-.+-.12 V) to drive the RS-232C is required, in addition to the power source (5 V) of the decoder.